Chemical heater



1,609,958 0. L. PERRAULT CHEMICAL HEATER Dec. 7 1926.

Filed March 5, 1923 IN VEN TOR BY ,5 ATTORNEYS Patented Dec. '1, 1926.

UNITED STATES PATENT OFFICE.

OF All-Fm, NEW YORK, ASSIGNOR TO CONSTANT HEAT PAC NEW YORK, ACORPORATION OF NEW YORK.

OSCAR L. PEBRAULT,

CORPORATION, OF ALBANY,

OHEKICAL HEATER.

Application flied larch a, 192:. Serial in. 622,505.

The invention relates to a chemical heater consisting of a containerpreferably of flexible rubberlike material, within .which are containedingredients adapted to produce heat by chemical reaction, whereby theheater will be suitable for purpgses similar to those for which hotwater ttles,'electric heating pads and the like are used.-

One object of the invention is to provide a heater of the above naturein which the degree of heat obtained may be accurately and reliablycontrolled, so that when the heater is used for sick room purposes, forexample, there will be no danger of the 16 temperature rising to a pointwhich might injure the patient.

Another object is to provide a heater in which the period duringwhich'the heat is nerated may be adequately controlled, and

20 t e heater readily and quickly cooled or heated as may be desired.

Another object is to provide a chemical heater as above described which,while being substantially impervious to the leakage of solid or liquidingredients contained therein, will nevertheless permit air to enter,and gases generated byv chemical action within the heater, to escapetherefrom, and

, without the liability of injuring surrounding objects.

Further objects and advantages of the invention will be in part obviousand in part specifically pointed out in the' description hereinaftercontained, which, taken in con- II nection with the accompanyingdrawings, discloses certain preferred embodiments thereof; be consideredas merely illustrative of its principle. In the drawings:

40 Fig. 1 is a plan view of a heater constructed in accordance with theinvention, with its flap raised from normal position.

Fig. 2 is a transve se se tional view of the structure shown' in Fig. 1,but with the flap in normal position.

Figs. 3 and 4 are respectively a plan view and a central section showingin detail the structure of the closure and associated parts of theheater.

The heat producing ingredients of the heater are carried by a container1 which I prefer to make of flexible rubberlike material, such aspara-rubber, which will be impervious to the action 'oftheheat-producing substances,

such embodiments, however,are to and which preferably is constructed inflat bag-like form whereby the container will be suitable for sick roompurposes similar to those for which a hot water bottle is customarilyemployed in that it will occu y but a small amount of space and will esufiiclently flexible to be applied to an invalid without causingdiscomfort.

A suitable charging opening for the container will be understood asassociated therewith, such opening in the present instance being locatedin the top wall 2 of the container, and bein provided with outer andnner neck mem ers 3 and 3 which are screwed together to clamp betweenthem the top wall 2- of the container. If desired, an annular head 4 maybe provided on wall 2, to assist in effecting a tight joint between thesame and the neck members above described. A cap 5 engages over the neckmembers 3 and 3* previously described, and effects a tight closure forthe container; this cap preferably is of dimensions rendering itsuitable to serve as a measure cup for the heat-producing ingredients.

I prefer to generate the heatwithin the container 1 by combining anammonia salt,

preferably ammonium chloride (NH,C1)

with comminuted iron and iron oxide in the presence of water. Certainother ingredients may be added if desired, such as co per oxide ordouble chloride of copper an ammonia, to cut down the amount of ammoniagas which otherwise might be given oil; also a water absorbent material,such as wood pulp,

' and perchlorite of iron. The above reagents may be advantageouslycombined in the following proportions by volume:

Parts.

Fe-FeO 20 53 .1 0 p 5 tot 2. CuO-C 1 'water throughout the container,and .the

escape of gas from all portions of the container to the chargingopening, as by providing a plurality of ,ribs 6 which radiate from thecharging' opening in such manner as to provide grooves or ducts betweenthem which are noteasily completely filled or obstructed by theheat-producing ingredients.

After the heater is placed in operation by mixing therein theheat-producing ingredients, the gas generated by the reaction should bepermitted to escape and a small amount of air should be permitted toenter the container. in the present form of the invention the container1 is gas and liquid tight except as permitted by the charging opening,and the cap 5 is arranged to serve the purposes above mentioned.

As shown, the closure 5 is provided with vent passages 7 which permitthe gas to escape and air to enter, but the passage there through ofliquid or solid material is obstructed by means of one or more screens 8of fine meshed wire or the like, and which are suitably held within theclosure, as by a metal ring 9 having holes 10 corresponding to passages7. A disk 10 of fine meshed fabric may also be employed in connextionwith the screen 8 to prevent the chemicals in the container from sittingout, the disk being preferably treated with formaldehyde, or the like tominimize deterioration thereof.

I prefer to cover the cap or closure 5 by means of a flap 10" which maybe of rubber and suitably secured to one edge 11 of the container, andsuch flap if deslred may be held in place by suitable devices such asthe rubber button 12 secured to wall 2 of the container, and engaging abuttonhole 13 in the flap. When the heater is in use a certain amount ofgas is given otf'therefrom which may contain moisture or chemicalcompounds which, if the flap be employed, will largely be deposited onthe inner surface thereof without wettingor injuring obiects surroundingthe container.

prefer to space the inside of the flap 1 0 from the vent passages 7 inthe closure, to a certain extent in order that/the flap will not preventthe gas from escaping from and air from entering the container. Asshown, a plurality of ridges 14 are provided on the flap, and thus thegas may pass out between the ridges, although the flap as a whole may beclose up against the container. Holes 16 may also be punched in the flapto allow the gas to escape and the air to enter the heater more fully.

I have found that the amount of heat given off by the heater with agiven mixture. is dependent primarily upon the amount of oxygen which ispermitted to enter the container, and therefore by regulating the amountof air, it is possible to keep the temperature of the container withindefinite limits; for example, if a screen 8 of mesh be employed, thetemperature with a given sized cap may range between 115 and 125 F..while if a 60 mesh screen were employed. a temperature of from 130 to145 F. will be obtained. Thus by calibrating a heater of given area ofopening and heat-producing mixture, according to the mesh of screenemployed, the heater may be relied upon to keep within certaintemperature limits. This is highly important, a heater being unsuitablefor hospital use (for example, if after being applied to an invalidthere is danger that its temperature might increase insufficiently tocause blistering or burning.

it will be obvious that the adjustment in size of screen above-mentionedis but one illustrative method of regulating the supply of oxygen to thecontainer.

it is also found that the chemical reaction within the container may bequickly stopped by ett'ecting an air-tight seal for the same;

as shown, a rubber gasket 15 (Fig. 4) is employed which may beinterposed between the closure 5 and the neck member 3. When the heateris again desired to be used the reaction may be started up very quicklyby removing the gasket 15 and agitating the mixture within thecontainer. Thus the ingredients within the heater need not be taken outor replaced even when the heater is desired for intermittent use, andthe operation of starting and stopping the heater is very simple;furthermore, the chemical mixture does not deteriorate to anysubstantial extent while the heater is not in use.

The presence of a water absorbent material, such as wood pulp or sawdust, or strips of filter paper 5 in the heat-producing mixture,promotes the action of the heater both from the standpoint of bringingabout a well distributed reaction therein, and acting as a carrier forthe water and ammonium chloride when the heater is not in use.

The present application is a continuation in part of my priorapplication Serial No. 571,981, filed June 30, 1922, entitledComposition for chemical heaters.

While certain specific embodiments of my invention have been disclosed,it will be obvious that many changes may be made therein withoutdeparting from its principle, as defined in the following claims:

I claim:

1. A chemical heater comprising a fluid tight container having acharging opening therein, a closure for such opening, a compound withinsaid container comprising iron and a salt adapted to react chemicallytherewith to produce heat upon the addition of water, and means wherebysaid closure may be adjusted to permit the escape of gases generatedwithin the container and ermit air to enter during operation of theeater.

2. A chemical heater comprising a container having a charging openingtherein, a compound within said container compris ing iron and a saltadapted to react chemically therewith to produce heat upon the additionof water, and means whereby a fluid tight seal for said container may beeffected.

3. A chemical heater comprising a container of fluid-tight materialhaving a charging opening therein, a closure normally in position oversuch opening, a compound within said container comprising iron and asalt adapted to react chemically therewith to produce heat upon theaddition of water, and means whereby said closure may be adjusted topermit the escape of gases generated within the container and permit airto enter during operation of the heater and while disposed over saidopening or to effect a fluid-tight seal for the container.

4. A chemical heater comprising a conlainer of fluid-tight materialhaving a charging opening therein, a compound within said containercomprising iron and a salt adapted to react chemically therewith toproduce heat upon the addition of water, and a closure for such openinghaving a vent passage therein adapted to permit the escape of gasgenerated within the container and permit air to enter during theoperation of the heater,

together with a sealing gasket adaptable to effect a fluid-tight sealwhen the closureis placed in operative position.

closure for said container, a flap member on said container adapted tooverlie said closure, means permitting the escape of gases from withinsaid container and permitting air to enter through said closure, andmeans for spacing the adjacent portion of said flap member from theclosure.

6. The combination set forth in claim 6 wherein the last mentioned meansis constituted by ridges on the interior of the flap member.

7. A chemical heater comprising a container of flexible liquid-tightmaterial having a charging opening therein in combination with interiorribs on the wall of the container extending from points adjacent saidcharging opening.

In testimony that I claim the foregoing, I have hereunto set my handthis 10th day of Feb., 1923.

OSCAR L. PERRAULT.

